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Variations in solar luminosity and their effect on the Earth's climate
Detailed analysis of small output variations in the Sun's total energy output has greatly advanced understanding, and this new understanding indicates that brightening of the Sun is unlikely to have had a significant influence on global warming since the seventeenth century. Expand
The behavior of solar magnetic plages measured from Mt. Wilson observations between 1915-1984
We describe the digitization and reduction of the daily solar chromospheric spectroheliograms obtained in the K-line of Ca II between 1915-1984 at Mt. Wilson Observatory. Our results provide theExpand
Magnetic modulation of solar luminosity by photospheric activity
The behavior of slow changes in solar irradiance S is studied using measurements obtained with radiometers on the SMM and Nimbus 7 spacecraft. The general downtrend in the radiometer readings isExpand
The pressure and energy balance of the cool corona over sunspots.
We study the extreme-ultraviolet (EUV) emission of the 22 largest sunspots observed with the ATM SO55 spectrometer. From their time behavior we infer that the pressure and energy balance of the coolExpand
Dimming of the 17th Century Sun
Reconstructions of total solar irradiance (TSI) rely mainly on linear relations between TSI variation and indices of facular area. When these are extrapolated to the prolonged 15th-17th centuryExpand
Do Changes in the Photospheric Magnetic Network Cause the 11 Year Variation of Total Solar Irradiance
Changes in the area of the photospheric magnetic network over the sunspot cycle have been put forward as the missing component required to explain the 11 yr variation of total solar irradianceExpand
A Stellar View on Solar Variations and Climate
The recent retraction of this stellar evidence and of the solar irradiance reconstructions based on it is discussed, which has important implications for the relative roles of various forcing factors in climate change. Expand
What Determines the Relative Areas of Spots and Faculae on Sun-like Stars?
We analyze newly digitized Ca K plage area data extending back to 1915, and also the white-light facular area data beginning in 1874, to investigate further our earlier finding that the area ratio ofExpand
A comparison of variable solar total and ultraviolet irradiance outputs in the 20th century
[1] Differences in time- variation between total and ultraviolet solar irradiance could help in separating their influence on climate. We present the first models based on area measurements ofExpand
Morphological relationships in the chromospheric Hα fine structure
A continuous relationship is proposed between the basic elements of the dark fine structure of the quiet and active chromosphere. A progression from chromospheric bushes to fibrils, then toExpand